Millions of miles of piping and millions of control valves are installed throughout the world. These valves control the flow of fluids and gas through pipes that route chemicals through refineries, storage facilities, underground, marine vessels and space. Pipes need repair and sometimes feature enhancements such as electric terminals for cathodic protection or mechanical fasteners for stairs, ladders and walkways. Valves are mechanical devices with moving parts. The moving parts wear out or corrode over time, causing leaks. With aging equipment fighting increased clean air, water and soil standards, the need for valve, pipe and pipe component repair is growing rapidly.
Many pipes, valves and pipe components contain chemicals that are volatile or caustic with unsafe leakage levels measured in parts per million (ppm). Not only are these chemicals hazardous to the environment, but also to the technicians who are repairing them.
When a valve begins to leak in a refinery, the refinery must be taken out of service, costing millions of dollars a day or the valve leak needs to be repaired while it is in-service. To do this, petrochemical service technicians, drill a hole partially through the valve housing near the gland packing, thread this hole and then screw on a fitting that will eventually allow drilling and injecting new sealant. This threading process is fraught with problems. First, if the technician drills too deep into the bell housing, he could be exposed to hazardous chemicals threatening his life. In addition, once the fitting is attached to the thin wall of the housing, it is secured by only a few threads. This makes the fitting subject to breakage in the harsh physical environment of a refinery. In addition, threads can become a point of leakage as corrosion and mechanical vibration weaken the connection. During the process of injecting new sealant into the valve, existing injection processes allow hazardous material to escape into the environment, exposing the repair technician to hazardous chemicals and violating ever tightening EPA rules.
In the past, if a fastener such as a stud, boss, nut, pin, screw, hinge, fitting, lever or clamp were attached to a pipe or valve, arc, MIG,TIG welding, GMAW, GTAW, FCAW or SMAW or oxy-acetylene torch brazing was utilized. Because of the high temperatures and sparks associate with these welding processes, they cannot be used in hazardous environments.